Evolution And History

Evolutionary Medicine 313

On a positive note, treatments can also be allowed to

flow freely. For example, Brazil’s HIV/AIDS program is in-

ternationally recognized as a model for prevention, educa-

tion, and treatment for several reasons. Through a national

policy of developing generic alternative antiretroviral agents

and negotiating for reduced prices on patented agents, in

1996 Brazil became the first country to guarantee free anti-

retroviral access to all its citizens. At the same time, Brazilian

public health officials developed counseling and prevention

programs in collaboration with community groups and reli-

gious organizations. Their AIDS program’s success is in part

due to the candid public education on disease transmission

targeted at heterosexual women and young people, who are

now the fastest-growing groups affected by HIV.

In 2004, Brazil continued its innovations with the South

to South Initiative providing assistance to the HIV and

AIDS programs in the Portuguese-speaking African coun-

tries of Mozambique and Angola. The Brazilian approach

of providing free antiretroviral agents and collaborating

with civil and religious groups to develop appropriate

counseling, education, and prevention programs has been

replicated directly in these African countries.^13

particularly those in the broccoli and cabbage family, nat-

urally contain toxins developed through the plants’ evo-

lutionary process to prevent them from being eaten by

animals. Profet suggests that eating these plants during the

first weeks of pregnancy, when the developing embryo is

rapidly creating new cells through mitosis and differenti-

ating into specific body parts, makes the embryo vulner-

able to mutation. Therefore, a heightened sense of smell

and lowered nausea threshold serve as natural defenses for

the body. Pregnant women tend to avoid these foods, thus

protecting the developing embryo.

Evolution and Infectious Disease

Understanding infectious disease is all the more important

in a globalizing world where people, viruses, and bacteria

cross national boundaries freely. Evolutionary medicine

provides key insights with regard to infectious disease.

First, if infectious disease is viewed as competition

between microorganisms and humans—as it is in bio-

medicine where patients and doctors “fight” infectious

disease—microorganisms possess one very clear advan-

tage. Viruses, bacteria, fungi, and parasites all have very

short life cycles compared to humans. Therefore, when

competing on an evolutionary level, they will continue to

pose new threats to health, because any new genetic vari-

ants appearing through a random mutation will quickly

become incorporated in the population’s genome. This

notion is of particular importance with regard to the use

of antibiotics to fight infectious disease.

While antibiotics do kill many bacteria, increasingly

resistant strains are becoming more common. “Resistant

strains” refers to genetic variants of a specific bacterium that

are not killed by antibiotics. If a resistant strain appears in

an infected individual who is being treated with antibiotics,

the removal of all the nonresistant strains essentially opens

up an entire ecological niche for that resistant strain inside

the infected human. Here, without competition from the

original form of the bacterium wiped out by the antibiotic,

this mutant can proliferate easily and then spread to other

individuals. The practice of taking antibiotics artificially al-

ters the environment inside the human body.

In order to avoid the development of resistant strains,

complex lengthy treatment regimes, often of multiple drugs,

must be followed exactly. These expensive treatments are

cost-prohibitive in many parts of the world. The unfortu-

nate result is not only increased human suffering but also

the possibility of creating environments for the development

of resistant strains as individuals receive partial treatments.

Another problem is that although individuals seek

treatment within their own country’s health care system,

infectious microbes do not observe these same national

boundaries. To eradicate or control any infectious process,

the world has to be considered in its entirety.

(^13) D’Adesky, A.-C. (2004). Moving mountains: The race to treat global AIDS.
New York: Verso.
Medical anthropologist Emily Martin has shown that scientific depic-
tions of infectious disease draw upon military imagery common to the
culture of the United States. Biomedical treatments involve taking
antibiotics to kill “invading” organisms. An evolutionary perspec-
tive suggests that the quick life cycle of microorganisms makes this
“battle” a losing proposition for humans.
© With permission from Alberta Heritage Foundation for Medical Research. Artist: Carla Andrews.
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